The Milwaukee Brewers players are wearing number 21 to honor Roberto Clemente, the legendary Puerto Rican Hall of Famer who wore No. 21 throughout his career. MLB celebrates Roberto Clemente Day by allowing players, especially Puerto Rican players and Roberto Clemente Award recipients and nominees, to wear No. 21 to commemorate his legacy and achievements. The number symbolizes Clemente's impact on baseball and his humanitarian contributions off the field. This tradition is part of broader celebrations during Hispanic Heritage Month and is observed across Major League Baseball.